678320 has 40 divisors (see below), whose sum is σ = 1614480. Its totient is φ = 264960.

The previous prime is 678299. The next prime is 678329. The reversal of 678320 is 23876.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 678320.

It is not an unprimeable number, because it can be changed into a prime (678329) by changing a digit.

678320 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4811 + ... + 4949.

It is an arithmetic number, because the mean of its divisors is an integer number (40362).

2⁶⁷⁸³²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 678320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (807240).

678320 is an abundant number, since it is smaller than the sum of its proper divisors (936160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

678320 is a wasteful number, since it uses less digits than its factorization.

678320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 207 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 678320 is about 823.6018455540. The cubic root of 678320 is about 87.8641153514.

The spelling of 678320 in words is "six hundred seventy-eight thousand, three hundred twenty".